03- compartment syndrome Flashcards
(18 cards)
What is the technical definition of compartment syndrome?
Compartment pressures within 30mmHg of the diastolic pressure
Diastolic pressure can vary intra-op, must be compared to the pre-op diastolic pressure
What is the accuracy of a Stryker needle?
Low rates of inter-observer reliability. Continuous intramuscular compartment pressure is more reliable
What are the 5P’s of compartment syndrome?
Pain, pallor, paresthesias, pulselessness, paralysis (weakness)
What is the most common cause of compartment syndrome?
Fracture 69%
What is the risk of ACS in tibial shaft fractures?
2.7-15.6% of tibial shaft fractures
What is the pathogenesis of compartment syndrome?
Local trauma, soft tissue destruction-> Bleeding and edema-> increased interstitial pressure->decreased venous outflow relative to arterial inflow -> myoneurial ischemia
What factors of tibial shaft fx are related to increased risk of compartment syndrome?
Diaphyseal fracture, young age (<20)
What are the nonoperative criteria for tibial shaft fracture
<5 degrees of varus/valgus
5-10 deg apex anterior/posterior
Rotation <10 deg
Shortening <1cm
What are the risks of a 2 incision approach?
Superficial peroneal nerve
Medial incision: saphenous vein , incomplete release of soles bridge
What happens to the leg from an untreated compartment syndrome?
Volkmans contractures with peds cavus, clawed toes
How long does a compartment syndrome take to develop?
Generally accepted that after 6-8 hours of inadequate muscle perfusion, necrosis develops
What are the 2 incisions?
Anterolateral 2cm anterior to the fibula for access to anterior and lateral compartments
Medial incision: 2cm posterior to the tibia for superficial and deep posterior compartments
What is the purpose of a Jacobs ladder?
Fasciotomy incisions can retract and be hard to close, helps decrease the size of the wound for closure or future soft tissue coverage
Why did you pre drill pins?
Lower peak insertion temp, less thermal necrosis and bone damage, some posit less loosening, although this is controversial
What is the most common complication of ex fix?
pin loosening or pin site infection
What factors increase the stability of an ex fix?
Most important: larger diameter pins
Additional pins, decreased bone to bar distance, pins in different planes, increased size of bar or stacking bars, bars in different planes, increased space between pins
What is the most important factor in overall stability of an ex fix construct?
Stability of the bone/pin interface
Bending stiffness of the pin=
Bending stiffness of the pin= radius of pin^4
